How to find engine control computer in 1992 Buick Skylark and fix it. on 1992 Buick Skylark

My car runs fine until it reaches operating temperature, then it quits running. I need to find out how get in there and see if the computer bad. It also has no spark after it stops, 10 to 15 minutes later it works again. Would this be caused by damage in circuits or motherboard?